Solve each system of equations by using either substitution or elimination. r + 4s = -8 3r + 2s = 6

Find the solution of each of the following.

Suppose a gym membership has an initial enrollment fee of $75 and then a fee of $29 a month. which equation models the cost, c, of the gym membership for m months?

This is a map of the mars exploration rover opportunity predicted landing site on mars. the scale is 1cm : 9.4km. what are the approximate measures of the actual length and width of the ellipse? i mostly need to know how to set it up : )